0 items - $0.00
No products in the cart.
Best Insulation for Vehicles Operating in Extreme Heat Conditions
Vehicles get hot, cold and loud, and most people try to fix all three with one product. That does not work, because heat and noise are different problems and the materials that solve them do different things.
This page explains which insulation does what, what order the layers go in, and what to use where. Kool Wrap has supplied heat and sound protection in Australia since 1995, to workshops, fleet operators, van builders and people working on their own car in the driveway.
The four materials, and what each one actually does
| Material | What it does | Where it goes |
|---|---|---|
| Sound deadening sheet | Adds mass so a panel cannot ring | Straight onto clean bare metal |
| Foam liner | Adds a thick, light layer that slows heat moving through | Over the deadener, or over bare metal |
| Foil bubble insulation | Reflects radiant heat before it reaches the surface | Behind lining panels, with the joins taped |
| Heat shield | Blocks heat radiating off a hot component | Between the hot part and whatever you are protecting |
Mass, thickness, reflection and shielding. Four jobs, four materials. Adding more of the wrong one never substitutes for the right one.
The order the layers go in
- Clean metal. Degrease it. Nothing adheres properly to oil or dust.
- Sound deadening sheets. Mass goes first, against the panel. Kool Wrap sheets are 50 x 32cm, around 2mm thick at 3kg per square metre, with an aluminium top layer.
- Foam liner. Our 10mm Van Liner is closed-cell foam with a foil face, self-adhesive, 1.0m x 5.0m. Cut it with scissors and press it on. It contours around curved panels, which is why it suits vehicle interiors rather than flat sheet.
- Foil bubble where there is an air gap. Reflective insulation needs a gap in front of it to work. Behind a lining panel is ideal. Straight under a carpet is not.
- Lining or trim back over the top.
Doing step 3 without step 2 is the most common mistake. Foam is light, and light materials do not stop a panel resonating.
Insulation for vehicle heat
Radiant heat from the sun
This is roof and wall heat, and it is a reflection problem. Foil bubble insulation is polyethylene bubble laminated to a silver foil on one side, 5mm thick, and it blocks up to 95 per cent of radiant heat. It is waterproof. Tape the joins so the moisture barrier stays continuous.
Radiant heat from the exhaust
This is a shielding problem, not an insulation one. Heat coming off a pipe under the floor is answered by an adhesive heat shield, which carries an embossed aluminium face on a fibreglass and polyester core and reflects up to 95 per cent of radiant heat. The 5mm heavy duty version is the one Kool Wrap recommends for under-car work where the exhaust heats the floor.
Never stick an adhesive heat shield directly onto an exhaust pipe, a manifold or a turbo housing. Shields go near heat, not on it. Anything that touches the pipe is exhaust wrap territory.
Engine bay heat
Under the bonnet, a combination of adhesive foam pads and compressed felt does both heat and noise at once. Our guide to under bonnet insulation covers what goes where.
Insulation for vehicle noise
Noise needs mass, and mass means a sound deadening sheet on the metal. Foam over the top helps, but only after the mass is there.
Start with the panels that ring: the floor, the door skins and the boot. The car door guide works through the first of those panel by panel, and car sound deadener explained covers what the material does and why mass is the mechanism.
Car insulation foam, and where it does not belong
Foam is the right answer inside a cabin, a canopy or a van, over the top of a deadening layer. It is the wrong answer anywhere near an exhaust system.
There is no foam that belongs against a hot pipe. Foam is a low-temperature material and putting it near exhaust heat is a fire risk, not an insulation strategy. If you need something that handles real heat, that is rockwool, rated up to 1,000 degrees Celsius and supplied in 5m rolls, or it is exhaust wrap, or it is a heat shield. Not foam.
Choosing insulation for your vehicle
| What you are solving | What to use |
|---|---|
| The cabin is loud on coarse roads | Sound deadening sheets on the floor, doors and boot |
| The roof or canopy gets hot in the sun | Foil bubble behind the lining, with taped joins |
| The floor is hot above the exhaust | 5mm heavy duty adhesive heat shield, underside of the floor |
| Cold mornings and condensation in a van | Foam liner over a deadening layer, walls and ceiling |
| Engine noise through the firewall | Deadening sheet on the cabin side, under bonnet insulation on the other |
| Heat radiating off a turbo or manifold | A turbo blanket or exhaust wrap, not insulation |
Questions about insulating a vehicle
How do I insulate a car for heat?
Work out whether the heat is radiant or conducted. Sun load through a roof wants a reflective layer with an air gap in front of it. Exhaust heat through a floor wants a shield fitted underneath. Cabin temperature generally wants a foam layer over a deadening layer.
What is the best insulation for a vehicle?
There is no single best one, which is why this page lists four. A vehicle that is loud and a vehicle that is hot need different products, and most builds end up using two or three together in the order set out above.
Can I use household insulation in a car?
Batts and building products are not designed for the vibration, moisture and temperature cycling inside a vehicle, and they do not stay where you put them. Use self-adhesive automotive material that is cut to fit and pressed on.
Do I need sound deadening and insulation, or just one?
Most vehicles want both, and in that order. Deadening stops panels ringing. Insulation slows heat. Neither does the other’s job.
Tell us what you are building
Call 1300 44 33 34 or email sales@koolwrap.com.au with your vehicle and what you are trying to fix. We ship Australia-wide with tracking sent after dispatch, from our office in Rowville, Victoria.
